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Implemented to/fromBin with tests passing
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@Nafees10
Nafees10 committed Jan 21, 2024
1 parent 7607a55 commit cfe9ff3
Showing 1 changed file with 52 additions and 83 deletions.
135 changes: 52 additions & 83 deletions source/navm/bytecode.d
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Original file line number Diff line number Diff line change
Expand Up @@ -147,86 +147,73 @@ unittest{
/// Returns: Expected stream size
private size_t binStreamExpectedSize(
size_t metadataLen = 0,
size_t instructionsCount = 0,
size_t dataLen = 0,
size_t labelsCount = 0){
size_t labelsCount = 0,
size_t dataLen = 0){
return 17 + 8 + metadataLen +
8 + (instructionsCount * 2) +
8 + dataLen +
8 + ((8 * 3) * labelsCount);
8 + ((8 + 8) * labelsCount) +
8 + dataLen;
}

/// Writes ByteCode to a binary stream
///
/// Returns: binary date in a ubyte[]
/*public ubyte[] toBin(ref ByteCode code, ubyte[7] magicPostfix = 0,
public ubyte[] toBin(ref ByteCode code, ubyte[8] magicPostfix = 0,
ubyte[] metadata = null){
// figure out expected length
size_t expectedSize = binStreamExpectedSize(
metadata.length, code.instructions.length, code.data.length,
code.labels.length);
metadata.length, code.labels.length, code.code.length);
// count label names sizes, add those
foreach (name; code.labelNames)
expectedSize += name.length;
ubyte[] stream = new ubyte[expectedSize];

// header
stream[0 .. 7] = cast(ubyte[])cast(char[])"NAVMBC-";
stream[0 .. 7] = cast(ubyte[])"NAVMBC-";
stream[7 .. 9] = ByteUnion!ushort(NAVMBC_VERSION).bytes;
stream[9 .. 16] = magicPostfix;
stream[9 .. 17] = magicPostfix;

// metadata
stream[16 .. 24] = ByteUnion!(size_t, 8)(metadata.length).bytes;
stream[24 .. 24 + metadata.length] = metadata;
size_t seek = 24 + metadata.length;
// instructions
stream[seek .. seek + 8] =
ByteUnion!(size_t, 8)(code.instructions.length * 2).bytes;
seek += 8;
foreach (inst; code.instructions){
stream[seek .. seek + 2] = ByteUnion!(ushort, 2)(inst).bytes;
seek += 2;
}
// data
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.data.length).bytes;
seek += 8;
stream[seek .. seek + code.data.length] = code.data;
seek += code.data.length;
stream[17 .. 25] = ByteUnion!(size_t, 8)(metadata.length).bytes;
stream[25 .. 25 + metadata.length] = metadata;
size_t seek = 25 + metadata.length;

// labels
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.labels.length).bytes;
seek += 8;
foreach (i, name; code.labelNames){
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.labels[i][0]).bytes;
seek += 8;
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.labels[i][1]).bytes;
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.labels[i]).bytes;
seek += 8;
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(name.length).bytes;
seek += 8;
stream[seek .. seek + name.length] = cast(ubyte[])cast(char[])name;
seek += name.length;
}

// instructions data
stream[seek .. seek + 8] = ByteUnion!(size_t, 8)(code.end).bytes;
seek += 8;
stream[seek .. seek + code.code.length] = code.code;
seek += code.code.length;

return stream;
}

///
unittest{
ByteCode code;/// empty code
ubyte[] bin = code.toBin([1, 2, 3, 4, 5, 6, 7], [8, 9, 10]);
assert(bin.length == 17 + 8 + 3 + 8 + 8 + 8);
ubyte[] bin = code.toBin([1, 2, 3, 4, 5, 6, 7, 8], [8, 9, 10]);
assert(bin.length == 17 + 8 + 3 + 8 + 8);
assert(bin[0 .. 7] == "NAVMBC-"); // magic bytes
assert(bin[7 .. 9] == [2, 0]); // version
assert(bin[9 .. 16] == [1, 2, 3, 4, 5, 6, 7]); // magic postfix
assert(bin[16 .. 24] == [3, 0, 0, 0, 0, 0, 0, 0]); // length of metadata
assert(bin[24 .. 27] == [8, 9, 10]); // metadata
assert(bin[9 .. 17] == [1, 2, 3, 4, 5, 6, 7, 8]); // magic postfix
assert(bin[17 .. 25] == [3, 0, 0, 0, 0, 0, 0, 0]); // length of metadata
assert(bin[25 .. 28] == [8, 9, 10]); // metadata
}

/// Reads ByteCode from a byte stream in ubyte[]
/// Throws: Exception in case of error
/// Returns: ByteCode
public ByteCode fromBin(ubyte[] stream, ref ubyte[7] magicPostfix,
public ByteCode fromBin(ubyte[] stream, ref ubyte[8] magicPostfix,
ref ubyte[] metadata){
if (stream.length < binStreamExpectedSize)
throw new Exception("Stream size if less than minimum possible size");
Expand All @@ -236,89 +223,71 @@ public ByteCode fromBin(ubyte[] stream, ref ubyte[7] magicPostfix,
throw new Exception("Stream is of different ByteCode version.\n" ~
"\tStream: " ~ ByteUnion!ushort(stream[7 .. 9]).data.to!string ~
"\tSupported: " ~ NAVMBC_VERSION);
magicPostfix = stream[9 .. 16];
size_t len = ByteUnion!(size_t, 8)(stream[16 .. 24]).data;
magicPostfix = stream[9 .. 17];
size_t len = ByteUnion!(size_t, 8)(stream[17 .. 25]).data;
if (binStreamExpectedSize(len) > stream.length)
throw new Exception("Invalid stream length");
metadata = stream[24 .. 24 + len];
size_t seek = 24 + len;
metadata = stream[25 .. 25 + len];
size_t seek = 25 + len;

ByteCode code;
// instructions
len = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
if (binStreamExpectedSize(metadata.length, len / 2) > stream.length)
throw new Exception("Invalid stream length");
seek += 8;
code.instructions = (cast(ushort*)(stream.ptr + seek))[0 .. len / 2];
seek += len;
// data
len = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
if (binStreamExpectedSize(metadata.length, code.instructions.length, len)
> stream.length)
throw new Exception("Invalid stream length");
seek += 8;
code.data = stream[seek .. seek + len];
seek += len;

// labels
len = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
if (binStreamExpectedSize(metadata.length,
code.instructions.length,
code.data.length, len) > stream.length)
if (binStreamExpectedSize(metadata.length, len) > stream.length)
throw new Exception("Invalid stream length");
seek += 8;
code.labels.length = len;
code.labelNames.length = len;
foreach (i, ref label; code.labels){
label[0] = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
seek += 8;
label[1] = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
label = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
seek += 8;
len = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
seek += 8;
if (seek + len > stream.length)
throw new Exception("Invalid stream length");
code.labelNames[i] = cast(immutable char[])stream[seek .. seek + len];
code.labelNames[i] = cast(immutable char[])stream[seek .. seek + len].dup;
seek += len;
}

// data
code.end = ByteUnion!(size_t, 8)(stream[seek .. seek + 8]).data;
if (binStreamExpectedSize(metadata.length, code.labels.length, code.end)
> stream.length)
throw new Exception("Invalid stream length");
seek += 8;
code.code = stream[seek .. $].dup;
return code;
}

///
unittest{
import std.functional, std.range;
ByteCode code;
ushort[] instructions = iota(cast(ushort)1, ushort.max, 50).array;
ubyte[] data = iota(cast(ubyte)0, ubyte.max).cycle.take(3000).array;
code.instructions = instructions.dup;
code.data = data.dup;
ubyte[] data = iota(cast(ubyte)0, ubyte.max).cycle.take(0).array;
code.code = data.dup;
code.labelNames = ["data", "start", "loop", "end"];
code.labels = [
[0, 0],
[2, 8],
[1025, 2020],
[1300, 3000]
0,
2,
1025,
1300,
];

ubyte[] bin = code.toBin([1, 2, 3, 4, 5, 6, 7], [1, 2, 3]).dup;
ubyte[7] postfix;
ubyte[] bin = code.toBin([1, 2, 3, 4, 5, 6, 7, 8], [1, 2, 3]).dup;
ubyte[8] postfix;
ubyte[] metadata;
ByteCode decoded = bin.fromBin(postfix, metadata);
assert(postfix == [1, 2, 3, 4, 5, 6, 7]);
assert(postfix == [1, 2, 3, 4, 5, 6, 7, 8]);
assert(metadata == [1, 2, 3]);
assert(decoded.instructions == instructions);
assert(decoded.data == data);
assert(decoded.labels.length == 4);
assert(decoded.labels[0] == [0, 0]);
assert(decoded.labels[1] == [2, 8], decoded.labels[1].to!string);
assert(decoded.labels[2] == [1025, 2020]);
assert(decoded.labels[3] == [1300, 3000]);
assert(decoded.labels == [0, 2, 1025, 1300]);
assert(decoded.labelNames[0] == "data");
assert(decoded.labelNames[1] == "start");
assert(decoded.labelNames[2] == "loop");
assert(decoded.labelNames[3] == "end");
}*/
assert(decoded.code == data, decoded.code.to!string);
}

/// Parses data
/// Throws: Exception if incorrect format
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